Former US President Ronald Reagan, who brought a blend of sunny optimism, right-wing politics and fierce anti-Communism to the White House, died yesterday of complications from Alzheimer's disease.
The actor turned president died at his Bel-Air home in California from pneumonia.
Former US President Ronald Reagan with his long-time ally, former British Prime Minister Mrs Margaret Thatcher
His death at 93, more than 15 years after leaving the White House and after a 10-year struggle with Alzheimer's that had kept him out largely of the public eye, prompted warm tributes from world leaders.
The Taoiseach, Mr Ahern, said he learned "with sadness" of Reagan's death. He said the former president was proud of his Irish heritage and his visit to Ireland in 1984 is "still remembered with great fondness by many here".
"President Reagan's interest in Irish affairs was invaluable in the period leading up to the signing of the Anglo-Irish Agreement in 1985," Mr Ahern said. He also commended Reagan for his important role in bringing an end to Communism and the artificial division of Europe after World War II.
The father of Soviet Perestroika reform, Mr Mikhail Gorbachev, praised Reagan, his partner on the world stage, as a great leader who dared to change the tide in relations between the Cold War superpowers. Mr Gorbachev told his dialogue with Reagan "kick-started the process, which ultimately put an end to the Cold War".
Former British Prime Minister Margaret Thatcher - the "Iron Lady" to Reagan's warm "Great Communicator" - called him a "truly great American hero".
"Ronald Reagan had a higher claim than any other leader to have won the Cold War for liberty. To have achieved so much, against such odds, and with such humour and humanity, made Ronald Reagan a truly great American hero," Mrs Thatcher said.
French president Mr Jacques Chirac called him "a great statesman who through the strength of his convictions and his commitment to democracy will leave a deep mark in history."
"A great American life has come to an end," US President George W. Bush said in Paris, where is meeting with Mr Chirac and attending 60th anniversary celebrations of the D-Day landing.
Hundreds of people carrying US flags and flowers made a makeshift memorial outside the Los Angeles-area funeral home where his body was being embalmed before taken to lie in state at the Reagan library.
The library sits on the crest of a California hillside not far from implanted pieces of the Berlin Wall - which he implored Mikhail Gorbachev in a famous speech to "tear down this wall".
Reagan will be given a presidential state funeral in Washington later in the week.
Members of his immediate family were at his bedside as he died, including his wife of 52 years, Nancy. He was no longer able to recognize or speak to loved ones because of Alzheimer's.
The death ended a long, painful last chapter in a close marriage. Just last month, Nancy Reagan made a rare speech in which she described her husband's last days suffering from Alzheimer's.
"Ronnie's long journey has finally taken him to a distant place where I can no longer reach him," she said, urging support for stem cell research to help cure the disease.
Flags across the country were ordered lowered to half mast in a sign of respect for the man who effected a late 20th Century revolution in American politics, helping make Republicans the ruling party and conservatism a mainstream political philosophy.
